The White Witch (Thysania agrippina) is one of the largest moths in the world. The wingspan of the largest known individual of this species — the distance between the tips of its fully extended wings — measures 30.8 cm. It is found in Central and South America, ranging from Mexico in the north to Bolivia in the south.
The species has been known for a long time. It was first mentioned and depicted in a drawing by German artist and natural history illustrator Maria Sibylla Merian as early as 1705. However, the caterpillar of this moth was incorrectly depicted in her illustration. Although the adult moth was well known and described, its eggs, caterpillars, and host plants in the wild had never been documented. It was not until 2025 that caterpillars of this species were discovered in Panama, revealing that they feed on plants from the legume family.
Where does the moth’s name come from?
The genus name Thysania is derived from the Greek word thysanos, meaning “fringe” or “tassel”. This refers to the wavy, fringed edges of its wings. The species name agrippina was given in honour of Agrippina the Younger, a historical figure of Ancient Rome and the mother of Emperor Nero. Naming species after historical and mythological figures was a popular tradition in biological nomenclature in the 18th century. The species was scientifically described in 1776 by Dutch entomologist Pieter Cramer.
Despite its dignified scientific name, this moth is known in English as the White Witch, while in Spanish it is called Mariposa de la muerte (“moth of death”). These names were not given by chance. In the mythology of Central and South American peoples, this large, greyish moth has often been portrayed as a sinister figure and an omen of death. In the beliefs of many Indigenous peoples of South America, these moths have been associated with the spirits of the dead.
This negative image developed because of the moth’s exceptional size, nocturnal lifestyle, and greyish coloration. Flying through the darkness, such a large moth can easily resemble a ghost.
